These factors include rules, regulations, policies, or laws. The discussion uses the Vermont juvenile justice system as a prototype and provides examples of the tertiary, secondary, and primary prevention of delinquent behavior. Tertiary prevention is the prevention of further delinquent behavior; secondary prevention, the prevention of delinquent behavior with youths at risk of becoming delinquent; and primary prevention, the use of prevention programs that apply to an entire population of people. The analysis departs from the traditional one-on-one programs that modify the behavior of potential offenders, their significant others, or their victims and broadens the focus to social policies. Policies discussed include targeting resources to youths on probation, providing more intensive services in less restrictive settings, reducing risk factors like poverty or neglect, improving education, and reducing the amount of media violence viewed by children. Data tables and 12 references.